Metal pipe



FIG. 1 is a top plan view of a metal pipe illustrating my design;

FIG. 2 is a bottom plan view of a metal pipe illustrating my design;

FIG. 3 is a front view of a metal pipe illustrating my design, with the back view being a mirror image thereof;

FIG. 4 is a side view of a metal pipe illustrating my design, with the other side being substantially the same;

FIG. 5 is a right side perspective of a metal pipe illustrating my design; and,

FIG. 6 is a left side perspective of a metal pipe illustrating my design. 

The ornamental design for a metal pipe, as shown and described. 